Nozzle means



Feb. 10, 1-970 E. w. HINES ET AL ,4

NOZZLE MEANS Filed July 8, 1968 2 She ets-Sheet 1 Feb. 10, 1970 Filed July 8, 1968 E. w. HINES ET AL 3,494,309

NOZZLE MEANS 2 Sheets-Sheet 2 J r/Mp INVENTOR? EUGENE max/v55,

7mm MGI QZ ma 1% if f US. Cl. 1107 1 Claim ABSTRACT OF THE DISCLOSURE In disposing of fluid waste material by combustion, a stream of the Waste fluid in passing to a combustion space (i.e., incinerator) is highly aerated by means of an eductor. Air alone, or gaseous fuel plus air, are entrained in the stream.

This invention relates to the art of fluid waste disposal through high-temperature combustion, e.g., as disclosed in US. Patent No. 3,357,375 to I. W. Brophy, and is concerned with an improved mode of operation and improved apparatus which make possible a substantial shortening of the dwell period of the atomized fluid in the combustion space of an incinerator.

According to the disclosure in the aforesaid U.S. patent, a fluid (or fluidized) waste material containing a combustible component is dispersed in a stream of primary air upwardly into the base of a vertical cylindrical elongated space, defined in part by refractory walls. Combustion of the combustibles of the airborne dispersed waste is initiated immediately upon its entry into the space to form a burning aeroform stream. The combustion is controlled to maintain a maximum temperature in the range 2800-3000 F., and the progress of the burning aeroform stream through the space is controlled through the imposition of a superatmospheric pressure to ensure a predetermined time of retention of the burning stream in said space. The burning aeroform stream is surrounded, from the bottom upwardly, by a mantle of secondary air protecting the refractory walls from waste material impingement thereon, which secondary air eventually is used for completing, in the uppermost part of the space, the pyro-decomposition of the waste material and its conversion into a gaseous reaction product free from smoke, odor and visible ash.

Heretofore, a waste fluid medium to be combusted has either (a) been forced at high pressure through atomizing-type nozzles or (b) been caused to flow through a nozzle at low pressure whilst high-pressure air has been used to effect the atomization of the fluid. However, in the burning of some oils and waste materials some solid matter may remain in suspension in said fluid, which solid matter in suspension precludes the use of a nozzle having a small enough opening to properly atomize the fluid. As a result, complete dependence customarily has been made on the atomizing air to produce the breaking up of the waste fluid into small enough particles to allow effective combustion to take place. Unless this air is supplied at fairly high pressures, a truly effective atomization does not occur.

In the case of incinerators designed to burn waste fluids, blowers are generally used to supply both the atomizing air and the primary combustion air. Use is made of blowers rather than compressors by reason of a matter of economy. The low pressure air supplied by blowers generally does not properly atomize the fluid wastes to be burned. It is therefore, a purpose of this invention to provide for at least partial atomization or United States Patent ice breaking up of the fluid to be burned prior to its contact with the low-pressure atomizing air.

An object of the present invention is to provide means for, and a mode of, materially increasing the rate and the efliciency of the high-temperature combustion. Another inventive object is to provide a procedure for greatly increasing gas-liquid contact as between the air (or other oxygen-containing and combustion-supporting gas), or air and gaseous fuel, and the waste fluid in the mixture introduced, through a suitable burner, into the combustion chamber of an incinerator. A further inventive object is to decrease materially the dwell time, in the combustion space of the incinerator, necessary for completing the combustion of the aeroform waste.

We have found that the heretofore recited, and other, inventive objects are realized by entraining in a stream of the fluid waste, passing to the burner of the incinerator, a myriad of air-gas bubbles thereby greatly multiplying the actual gas-liquid contact area with consequent acceleration of the combustion. We bring about this very substantial entrainment of gas (i.e., of air plus gaseous fuel, or of air alone in the event the fluid waste contains a sufliciently high content of combustible components to make unnecessary the purposeful addition of a fuel) by passing the stream of fluid waste through an eductor utilizing the aspirator principle of a high velocity fluid entraining gas therein.

The aspirating eductor may be integrated into the burner per se of the incinerator, or it may be located any where along the course through which the waste fluid is forced to the burner. In other words, the aspiration of air-gas into the fluid may take place anywhere between the pump and the burner, including within the latter.

The invention will now be further described in the following and with reference to the accompanying draw in g, in which:

FIG. 1 is a diagrammatic representation of one embodiment of the invention, showing a system for feeding a stream of fluid waste to an atomizing means in the base of a combustion space, e.g., the combustion chamber of an incinerator, the aspirating eductor being integrated into the burner of the incinerator;

FIG. 2 diagramatically represents a modification of the apparatus of FIG. 1, in which a nozzle replaces the burner shown in FIG. 1 and in which the aspirating eductor is interposed into the feed line to the nozzle (the incinerator per se not being indicated);

FIG. 3 is similar to FIG. 2 except for the particular pump means employed for forcing fluid waste to the nozzle;

FIG. 4 diagrammatically represents an apparatus similar to that shown in FIG. 3 but differing therefrom in that the nozzle has been supplanted by a burner which includes an aspirating eductor;

FIG. 5 diagrammatically represents an apparatus similar to that shown in FIG. 3 except for the means for introducing air and gaseous fuel into the eductor; and

FIG. 6 diagrammatically represents a further modification of the apparatus shown in FIG. 1, featuring the interposition of the aspirating eductor in the line between the pump and the branch pressure line by which excess fluid is returned to the storage tank.

Having reference now to the several diagrammatically shown embodiments, and in particular to FIG. 1, it will be noted that fluid enters pump 10 via suction line 11 from storage tank 7. Fluid lea-ves pump 10 by way of main pressure line 12 and in this particular embodimentby reason of the fact that the pump over-pumps-a portion of the pumped fluid is returned to storage tank 7 via branch pressure line 12' by the opening of pressure relief valve 5 flow then taking place through return line 6. That portion of the fluid that is not thus by-passed flows via main pressure line 12 through screening device 9 and regulating valve 8 and finally to and through eductor 1, which latter has its exit flow pattern controlled in effect by ball 4. It should be noted that ball 4 is not an absolute requirement for operability of the apparatus and process. As the fluid waste passes through eductor 1, air is aspirated through port 3, becoming entrained in and intimately associated with the fluid in the difluser section of the eductor. The fluid exiting from the eductor is thus filled with millions of small air bubbles. The atomizing air (hereinafter referred to as primary air) flowing upward through the annular channel 40 encounters the already partially atomized mixture of air and fluid and therefore finds it much easier to complete the atomization of the fluid.

The modified embodiment shown in FIG. 2, an ordinary nozzle 20 has been used in place of the eductor 1 of FIG. 1, the nozzle being a part of a conventional burner which is more particularly illustrated in FIG. 6 hereof.

An eductor 1' is located in main pressure line 12 in advance of said nozzle 20, thus showing the versatility of its positioning. In this embodiment (FIG. 2) pump pumps a stream of fluid waste through screening device 9 and flow regulating valve 8 and thence through eductor 1' the entrainment of air being made through port 3 of this eductor. The resulting mixture of air and fluid flows to nozzle and is further mixed with atomizing air as in FIG. 1.

Having reference now to FIG. 3, use is made of a motor speed reducer pump combination 10' (hereinafter called infinitely variable displacement (i.v.d.) pump) which latter eliminates the use of the by-pass return to storage tank 7 by reason of the fact that the displacement of the pump may be infinitely varied by conventional control means (not shown). It should be further noted the use of a flow regulating valve this organization has been eliminated. The fluid flows through screening device 9 and thence to and through eductor 1', air being entrained through port 3. The resulting air-entrained fluid then enters nozzle 20, the air-fluid mixture thus emitted coming into contact with atomizing air as in FIG. 1.

With reference now to FIG. 4 it should be noted that the eductor 26 assumes again the position of the nozzle of FIG. 3, but that the combination of the parts in different than that disclosed in connection with the description of FIG. 1. In this embodiment pump 10' has infinitely variable displacement so that a flow control valve is not required in the pressure line nor is a by-pass line such as that previously described necessary.

It should be stated here, and as a generality, that the atomized material introduced into the combustion space must of necessity contain or include sufficient combustibles to carry out a thorough-going combustion of the Waste fluid. Frequently, the waste fluid thus to be disposed of contains waste oily components which are combustible and which are present in amount sufiicient to support the desired combustion. However, it is not unusual that the fluid waste to be disposed of is deficient in combustibles, in which event combustibles must be added to meet such deficiency. In such case, the added combustible may take the form of added carbonaceous or hydrocarbonaceous fuel or fuel oil (e.g. powdered coal, or fuel oil, or equivalent fuel) and may be introduced into the waste fluid at the storage tank or at some locus along the route from tank to burner. However, according to the present invention, recourse to the use of an eductor makes it particularly feasible to add necessary fuel in the form of a gaseous fuel (e.g., natural gas; city gas; or the like) along with the air aspirated by the eductor.

Having reference now to FIG. 5 pump 10 has infinitely variable displacement. The flow of fluid waste through the eductor 1" in this instance entrains through suction port 3' both air (air line 33) and fuel gas (valved supply line 34). In many instances, the entrainment of both air and fuel gas still further enhances the efficiency of combustion of the final atomized fluid.

With reference to FIG. 6, the pump 10 in this instance does not have variable displacement, and it does displace more of the waste fluid to be burned than is required, so that a portion of the displaced fluid is returned, via branch pressure line 12" pressure relief valve 5 and return line 6, to tank 7. The eductor 1 interposed in main pressure line 12, entrains air through port 3. A portion of the fluid passed through eductor 1 is returned to tank 7 as above stated, whilst the remaining part of the fluid shown flows through screening device 9, regulating valve 8 to nozzle 44. Here, again, the atomizing air in the annular channel 40 further atomizes the fluid-air mixture. It should be noted that some desirable agitation and circulation results in tank 7 by the release of the entrained air, in the returned fluid, in the body of waste fluid in said tank.

Finally, it should be remarked that the above described systems generally should include provision not only for (a) aspirating air and (b) primary air but also for a separate supply of (c) secondary air, which secondary air is to be introduced, into the lower part of the combustion space, as an annular curtain surrounding the aeroform column eminating from the burner. Reference is had, in this connection, to the aforesaid Patent No. 3,357,375 for its discussion of the role of such curtain of second ary air.

We claim:

1. In the process of pyro-decomposition a fluid waste material, to convert the same into gaseous fully decomposed reaction products, involving dispersing with primary air a fluid waste material including a combustible component causing the combustible of the resulting aeroform mixture to burn in suspension, controlling the combustion to maintain a temperature suitable for the pyrodecomposition of the fluid waste, surrounding the burning aeroform mixture with a mantle of secondary air, and retaining the burning aeroform mixture at decomposition temperature for a time interval suflicient to ensure complete decomposition, the improvement which consists in shortening the retention time interval by materially entraining a combustion-supporting gas with said fluid waste before the same is dispersed with primary air.

References Cited 7 UNITED STATES PATENTS 3,357,375 12/1967 Brophy 7 KENNETH W. SPRAGUE, Primary Examiner 

